JP2007001458A - Mooring type balloon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mooring type small sized balloon capable of retaining an observation equipment such as a small sized camera in the sky and having a stabilized position. <P>SOLUTION: The mooring type balloon has a front area 15, a rear area 17 and a body area 16 for connecting the front area 15 and the rear area 17 and has a shape that an area of a border surface of the front area 15 and the body area 16 is larger than an area of a border surface of the rear area 17 and the body area 16 and an area of a cross section of the body area 16 is gradually reduced from the front area 15 to the rear area 17. The mooring type balloon has a string member 18 positioned in the mooring type balloon and fixed to a balloon skin of an upper part of the body area 16 and the string member 18 is constituted by an elastic body. The mooring type balloon retains the shape by pulling the balloon skin of the upper part of the body area 16. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

    The present invention relates to a tethered balloon, and more particularly to a tethered balloon for acquiring a high-altitude image that is not easily affected by wind.

  When a major earthquake, tsunami, or earth and sand disaster occurs, it is important to quickly grasp the damage situation at the site. Conventionally, helicopters have been dispatched urgently for the purpose of grasping the damage situation from the sky during disasters such as large earthquakes. However, the use of helicopters has the following problems.

  The first is that helicopter deployment is rarely completed within 30 minutes after the earthquake, which is most important for evacuation and rescue operations. The second is that the noise caused by the hovering of the helicopter blocks the transmission of the voice of those who are waiting for relief, making rescue operations difficult.

  In order to solve these problems, the use of balloons has been studied, but conventional balloons for high altitude shooting can cope with the increase in size of balloons to obtain sufficient buoyancy to overcome the effects of crosswinds. (For example, Patent Document 1).

  However, in order to be able to move with a cart or the like in an emergency, it has been desired to develop a small balloon that can be lifted with a small amount of gas cylinder that can be moved manually. However, the buoyancy is proportional to the cube of the size, whereas the force given by the cross wind is proportional to the square of the size. Therefore, in the small balloon, the influence of the cross wind cannot be ignored.

  On the other hand, in order to solve the problem of wind noise and engine noise of the wing during hovering, the use of an electric small unmanned helicopter has been attempted, but since the power source depends on a small battery, the hover time is limited, Moreover, the big problem was left in the load of the camera and the communication equipment.

Power supply to balloons and the like that rise above the sky has been attempted by wire from the ground for low altitude lighting, but at high altitudes, there is a risk of secondary disasters due to lightning strikes and high pressures caused by unforeseen winds. Including the possibility of contact accidents such as wire, it was not suitable for emergency use.
JP 2000-326899 A

  The present invention has been made to solve such a problem, and provides a tethered small balloon that can hold an observation device such as a small camera in the sky and is not easily affected by crosswinds. With the goal.

  A tethered balloon according to an aspect of the present invention is a tethered balloon having a body region that connects a front region, a rear region, the front region, and the rear region, and an area of a boundary surface between the front region and the body region is It is larger than the area of the boundary surface between the rear region and the main body region, and the cross-sectional area of the main body region has a shape that gradually decreases from the front region to the rear region, and is formed of an elastic body. It has a string member located inside and fixed to a ball skin at the upper part of the main body region, and the string member holds the shape by pulling the ball skin at the upper part of the main body region. is there. In the tethered balloon of the present invention, by pulling the upper part of the main body region with a string member and forming a balloon having the above-mentioned shape, it is possible to obtain buoyancy due to wind and to reduce the influence of wind. Become.

  According to the tethered balloon according to the present invention, the change angle due to the crosswind of the inclination angle of the tether rope for tethering the balloon to the ground can be reduced, and the string member expands and contracts due to the magnitude of the crosswind. Since the flow of the wind blown to the tethered balloon can be smoothed, the position of the balloon can be stabilized.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. In the tethered type balloon according to the present embodiment, a middle suspension mechanism for pulling the upper surface of the balloon with a string member is provided.

  The shape of the balloon is changed by the suspension mechanism, and a difference between the flow velocity of the wind flowing along the upper surface of the balloon and the flow velocity of the wind flowing along the lower surface of the balloon is generated. The difference in the external pressure between the upper surface of the tethered balloon and the lower surface of the tethered balloon is created by the difference in the flow velocity of the wind, other than the buoyancy due to the density difference between the gas inserted in the tethered balloon and the gas outside the tethered balloon, The buoyancy by wind can be obtained.

  The buoyancy of the wind makes it possible to reduce the change due to the crosswind of the inclination angle of the tethering rope for tethering the tethered balloon to the ground, and the position of the tethered balloon is stabilized. Further, the flow of the wind blown to the tethered balloon is smoothed by the expansion and contraction of the string member used for the hanging mechanism due to the size of the cross wind, so that the position of the tethered balloon is stabilized.

  Furthermore, in order to reduce the influence of the crosswind by this buoyancy, the weight must be reduced. Therefore, in the balloon according to the present embodiment, in order to reduce its own weight, a lightened fiber such as a polyester fiber is used for the ball skin.

  The balloon here is a flying device that floats a gas lighter than air in an airtight bag, and the tethered balloon is specified by being pulled from the ground by a tethering rope. It is a balloon. For example, a tethering rope is wound around a winch placed on the ground, and a balloon is connected to the tethering rope to raise the air.

  First, the shape of the tethered balloon according to the present embodiment in which wind is blowing from a predetermined direction will be described. FIG. 1 shows a cross-sectional view of a tethered balloon according to the present embodiment. The upper left figure is a sectional view as seen from the predetermined direction, the upper right figure is a sectional view perpendicular to the predetermined direction, and the lower figure is a sectional view as seen from vertically above.

  When the balloon is floating horizontally, the uppermost part is the uppermost part 11, the wind receiving part is the tip part 12 first, and the part located on the opposite side of the tip part 12 is the rear part. The bottom part 14 is the part located on the side opposite to the end part 13 and the top part 11 and located at the bottom when the balloon is floating horizontally.

  Further, a region from the front end portion 12 to a surface that is perpendicular to the wind direction and includes the uppermost portion 11 is defined as a front region 15. Further, a region from the rear end portion 13 to the plane perpendicular to the wind direction including the end on the rear end side of the bottom portion 14 is a rear region 17, and a portion other than the front region 15 and the rear region 17 is a main body region. 16

  As shown in the upper right view of FIG. 1, the cross-sectional view seen from the direction perpendicular to the wind receiving direction is as follows from the front end 12 to the rear end 13. The upper surface gradually rises and the lower surface gradually descends toward the boundary surface of the main body region 16, and the distance between the upper surface and the lower surface increases.

  The distance between the upper surface and the lower surface is maximized at the boundary surface between the front region 15 and the main body region 16. At this time, the front region 15 becomes a curved body whose cross-sectional area increases smoothly from the front end portion 12 to the boundary surface between the front region 15 and the main body region 16.

  In the main body region 16, the upper surface of the balloon from the boundary surface between the front region 15 and the main body region 16 gradually descends from the uppermost portion 11 while drawing a smooth curve. At this time, the cross-sectional area of the cross-sectional shape gradually decreases from the front region 15 to the rear region 17, and the cross-sectional area is minimized at the boundary surface between the main body region 16 and the rear region 17.

  Since the vortex makes the position of the balloon unstable, the generation of the vortex must be suppressed in order to stabilize the position of the balloon. In the tethered balloon according to the present embodiment, the upper surface of the balloon descends while drawing a smooth curve, thereby preventing the wind flowing along the upper surface of the balloon from creating a vortex.

  Further, a recessed portion 19 is preferably formed on the upper surface of the main body region 16. The recessed portion 19 is a portion that is recessed in a concave shape with respect to a straight line connecting the upper surface of the front region 15 and the upper surface of the rear region 17. By doing so, it is possible to increase the flow velocity of the wind flowing along the upper surface of the balloon. As a result, the difference in external pressure between the upper and lower surfaces of the balloon can be increased, and a larger buoyancy due to wind can be obtained.

  Further, in the upper right view of FIG. 1, the bottom portion 14 corresponding to the lower portion of the main body region 16 is preferably a substantially horizontal straight line. That is, it is preferable that the bottom 14 of the balloon is horizontal in a state where the balloon is floating. This is so that the wind flowing along the lower surface of the balloon flows smoothly without being affected by the balloon.

  Then, from the boundary surface between the main body region 16 and the rear region 17 to the rear end portion 13, the upper surface gradually decreases, the lower surface gradually increases, and the distance between the upper surface and the lower surface decreases. In addition, at the boundary surface between the main body region 16 and the rear region 17, the distance between the upper surface and the lower surface is minimized. At this time, the rear region 17 becomes a curved body whose cross-sectional area decreases smoothly.

  Next, in the cross-sectional view as seen from the direction of receiving the wind, as shown in the upper left diagram of FIG. Moreover, in the upper left figure of FIG. 1, the cross-sectional view in the AA 'part of the upper right figure of FIG. 1 is shown by the dotted line. In the main body region 16, since a suspending mechanism, which is a mechanism for pulling the surface of the balloon with a string member, is provided, the shape is a dotted line. Details of the hanging mechanism 18 will be described later. Moreover, in the cross-sectional view seen from the direction which receives a wind, it has a symmetrical shape.

  In the cross-sectional view seen from above, the width of the front region 15 increases toward the boundary surface between the front region 15 and the main body region 16 as shown in the lower diagram of FIG. In the main body region 16, the width gradually decreases from the boundary surface between the front region 15 and the main body region 16 to the rear end portion 13. In the cross-sectional view seen from above, it has a symmetrical shape.

  In order to create a balloon having the shape as described above, a suspension mechanism 18 is provided in the main body region 16 in the balloon according to the present embodiment. In order to create a balloon having the shape as described above, the hanging mechanism 18 is a string member made of a material having higher elasticity than the ball skin, as indicated by a dotted line in the upper right view of FIG. It is a mechanism that adheres to and pulls on the upper and lower ball skins. As an example of this string member, there is a string member made of raw rubber when polyester fiber is used for a balloon skin.

  This string member is preferably fixed on the center line of the cross section parallel to the wind receiving direction and parallel to the horizontal plane. By doing so, the cross section perpendicular to the direction of receiving the wind of the balloon can be made symmetrical, and the influence of the wind blowing can be limited to the upper and lower surfaces of the balloon.

  This is because if the force received by the wind is different on the left and right of the cross section perpendicular to the wind receiving direction, the balloon will rotate. The center of the cross section parallel to the wind receiving direction and parallel to the horizontal plane By fixing the string member on the line, rotation of the balloon can be suppressed.

  Further, in order for the above-mentioned balloon to face a certain direction with respect to the direction of the wind, it is preferable to provide the tail part 20 or the auxiliary tail part 21 in the rear region 17. Even if the tail portion 20 is not provided, when the wind direction changes in the cross-sectional direction in the upper right view of FIG. 1, the tip 12 is directed in the wind direction, but this operation is performed faster. For this purpose, the rear region 17 may be provided with the tail unit 20 or the auxiliary tail unit 21 having a plane parallel to the cross-sectional direction in the upper right view of FIG.

  Moreover, the string member used for the hanging mechanism 18 may be fixed to the inner ball skin in the vicinity of the outer ball skin provided with the string member for anchoring the balloon from the ground. This is to keep the bottom 14 horizontal by pulling with the same force as the bottom 14 of the ball skin is pulled by the string member used for the hanging mechanism 18.

  FIG. 2 shows changes in the shape of the tethered balloon according to the present embodiment depending on the flow velocity of the wind. FIG. 2 also shows a tether rope 23 for tethering and a plurality of branch ropes 24 to the tether rope 23. The string member used in the suspension mechanism 18 is shortened when the flow velocity of the wind is low, the size of the recessed portion 19 of the ball skin located in the main body region 16 is increased, and buoyancy due to the flow velocity difference is kept large. Can do. A light weight pipe 22 may be attached under the bottom portion 14. By installing a plurality of branch ropes 24 to the anchoring rope 23 by installing this pipe 22, the plane of the bottom portion 14 is maintained, and deformation is limited only to the recessed portion 19 at the upper part of the balloon. The pipe 22 is made of, for example, polycarbonate. The pipe 22 may be attached to the bottom portion 14 or may be attached to the tether rope 23.

  On the other hand, when the flow velocity of the wind is high, the string member used for the hanging mechanism 18 extends. This is because the air pressure outside the balloon is reduced by the wind and the internal pressure becomes higher than the external pressure, so that the balloon expands.

  Due to the expansion of the balloon at this time, the indented portion 19 of the ball skin located in the main body region 16 becomes smaller because the string member used for the hanging mechanism 18 extends. Therefore, the instability of the position due to the separation of the air flow due to an excessive flow velocity difference and the stall can be prevented in advance.

  Further, as described above, the suspension mechanism 18 operates also as a safety valve that prevents the balloon from being broken, so that it can flexibly cope with a change in the volume of the internal gas that accompanies changes in temperature and pressure. This eliminates the need for a mechanism for adjusting the internal pressure of the balloon, for example, a baronet blower, and thus eliminates the need for calculating the weight of the mechanism for adjusting the internal pressure of the balloon.

  Therefore, a mechanism for adjusting the internal pressure of the balloon that becomes an obstacle in reducing the weight of the small balloon becomes unnecessary, and the vertically upward force can be substantially increased. Therefore, the influence with respect to a cross wind can be reduced.

  Furthermore, the ball skin of the tethered balloon may be composed of an elastic body lower than the string member. This can have the change in the shape of the balloon due to the magnitude of the wind as described above, by controlling the shape of the tethered balloon with the string member.

  The effect by having said shape is demonstrated below. FIG. 3 shows how the wind passes when the wind blows on the balloon. FIG. 3A shows a balloon according to the present embodiment, and FIG. 3B shows a conventional spheroidal balloon.

  In the balloon according to the present embodiment, wind flows along the recessed portion 19 on the upper surface of the main body region 16. Further, since the lower surface of the main body region 16 is substantially in the same plane, the wind flows in the horizontal direction.

  As a result, in the main body region 16, a difference occurs between the speed of the wind flowing along the upper surface of the balloon and the speed of the wind flowing along the lower surface of the balloon. The speed of the wind flowing along the balloon upper surface is higher than the speed of the wind flowing along the balloon lower surface. This means that, from Bernoulli's theorem, the external pressure on the upper surface of the balloon is lower than the external pressure on the lower surface of the balloon. This atmospheric pressure difference causes buoyancy Fb due to wind.

  In FIG. 3, the force applied to the balloon is also described. In the balloon according to the present embodiment, the buoyancy Fh generated by the density of the gas inside the balloon and the external gas, the weight Fg of the balloon itself, the force Fw due to the cross wind, and the buoyancy Fb due to the wind are applied.

  As a comparative material, a spheroidal balloon used in a conventional balloon is shown in FIG. In the case of a spheroid-shaped balloon, since the flow velocity of the wind flowing on the upper surface and the lower surface is equal, there is no difference in air pressure between the upper surface and the lower surface. Therefore, buoyancy Fb due to wind does not occur.

  Therefore, the force applied to the spheroid balloon is the buoyancy Fh generated by the density of the gas inside the balloon and the outside gas, the weight Fg of the balloon itself, and the force Fw caused by the cross wind. That is, the difference between the balloon according to the present embodiment and the conventionally used spheroid balloon is whether or not there is buoyancy Fb due to wind.

  As described above, in the tethered balloon according to the present embodiment, the vertically upward force is larger than that of the conventional spheroidal tethered balloon. This means that when the crosswind velocity changes, the vertical upward force is larger than that of the conventional spheroidal balloon, so the change in the inclination angle of the tether rope to anchor the balloon due to the crosswind to the ground is reduced. This can be said that the tethered balloon according to the present embodiment is a balloon that is not easily affected by the crosswind, and at the same time, that can stabilize the position of the balloon.

  These tethered balloons are pulled by a string member from the ground when observation is performed by a camera or the like placed in a balloon. FIG. 4 shows the position P1 of the tethered balloon according to the present invention, which is tethered to the ground point G, and the position P2 of the conventional spheroid balloon, which are tethered to the ground point G by a sufficiently thin thread with negligible mass and wind resistance. ing.

  As described above, in the balloon according to the present embodiment, the force applied to the balloon includes the buoyancy Fh generated by the density of the gas inside the balloon and the outside gas, the weight Fg of the balloon itself, and the force caused by the cross wind. Since it is Fw and the buoyancy Fb caused by the wind, it suffices if the resultant force and the tension T1 of the tether rope are balanced.

  On the other hand, in a spheroid balloon used in a conventional balloon, the force applied to the balloon includes the buoyancy Fh generated by the density of the gas inside the balloon and the density of the outside gas, and the weight Fg of the balloon itself. Since the force Fw is due to the crosswind, the resultant force and the tension T2 of the tethering rope are in balance.

  In order to maintain this balance, the angle from the vertical angle must be θ1 in the balloon according to the present embodiment, and θ2 in the conventional spheroid balloon. Don't be. The inclination angles θ1 and θ2 are determined by the magnitude of the cross wind.

  Further, the difference between the inclination angles θ1 and θ2 is caused by the difference in whether or not there is buoyancy Fb due to wind. Since the balloon according to the present embodiment has the buoyancy Fb caused by the wind, the upward force in the vertical direction is increased, so that the inclination angle θ1 is smaller than the inclination angle θ2.

  FIG. 3 also shows the position P3 of the tethered balloon according to the present invention that is tethered to the point G on the ground when the cross wind increases, and the position P4 of the conventional spheroid balloon. In the balloon according to the present embodiment, since the upward force in the vertical direction is large, even if the force Fw due to the crosswind increases, the change amount Δθ1 of the tilt angle θ1 due to the crosswind is larger than the change amount Δθ2 of the tilt angle θ2. Less.

  This effect is even more pronounced in the case of a small balloon where the buoyancy due to the gas density difference is relatively small relative to the crosswind force. In the limit, for a kite that does not have buoyancy due to a difference in gas density, Fh = 0. Therefore, the vector sum of the buoyancy Fb caused by the wind, the force Fw caused by the cross wind, and the weight Fg of the kite is balanced with the tension of the tethering rope. However, it is clear that the height of the kite cannot be maintained in a shape where buoyancy cannot be obtained.

  From the above, by creating a balloon having a shape as shown in FIG. 1 with the suspension mechanism 18, it is possible to hold an observation device such as a small camera that is hardly affected by the magnitude of the wind in the sky. In addition, it is possible to create a tethered small balloon that is not easily affected by wind.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Further, in the above description, the case where the recessed portion 19 is present in the main body region 16 has been described. However, even if the recessed portion 19 is not present, the effect of the hanging mechanism 18 is not changed.

Sectional view of a tethered balloon according to the present embodiment Changes in shape of the tethered balloon according to the present embodiment due to the magnitude of the wind velocity How the wind passes against the balloon when the wind blows The position of the conventional spheroid balloon anchored on the ground by a sufficiently thin thread with negligible mass and wind resistance, and the position of the anchor balloon according to the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Top part 12 Tip part 13 Rear end part 14 Bottom part 15 Front area | region 16 Main body area | region 17 Rear area | region 18 Mechanism 19 Recessed part 20 Tail part 21 Auxiliary tail part 22 Pipe 23 Anchoring rope 24 Branch rope

Claims (9)

A front region, a rear region, and a main body region connecting the front region and the rear region;
The area of the boundary surface between the front region and the main body region is larger than the area of the boundary surface between the rear region and the main body region,
A tethered balloon having a shape in which a cross-sectional area of the main body region gradually decreases from the front region to the rear region,
A string member located inside the tethered balloon and fixed to the upper skin of the main body region;
The string member is a tethered balloon that is formed of an elastic body and holds the shape by pulling the ball skin on the upper part of the main body region.   The tethered balloon according to claim 1, wherein the string member pulls a ball skin on the upper part of the main body region of the tethered balloon to form a hollow portion on the upper portion of the main body region.   The tethered balloon according to claim 2, wherein when the flow velocity of the wind blown to the tethered balloon is high, the indented portion is reduced, and when the flow velocity of the wind blown to the tethered balloon is slow, the depressed portion is increased.   The tethered balloon according to any one of claims 1 to 3, wherein the spherical skin is formed of an elastic body that is lower than the string member.   The tethered balloon according to any one of claims 1 to 4, wherein a bottom portion between the front region and the rear region is horizontal.   The tethered balloon according to any one of claims 1 to 5, wherein the string member is fixed on a center line extending from the front region to the rear region of the tethered balloon.   The tethered balloon according to any one of claims 1 to 6, wherein a tail portion or an auxiliary tail blade that maintains a direction with respect to a wind direction is provided in the rear region.   The tethered balloon according to any one of claims 1 to 7, further comprising a pipe attached to a bottom part of the tethered balloon or a tethering rope for tethering the tethered balloon. The anchoring type according to any one of claims 1 to 7, wherein a position of an anchoring rope for anchoring the anchoring balloon and a position on the ball skin to which the string member is fixed are the same. balloon.

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